Diagnosis control method of air conditioner

ABSTRACT

A diagnosis control method of an air conditioner is provided to clearly inform a user of an air conditioner installation error. The diagnosis control method includes receiving a test run command or a self-diagnosis command for diagnosis of the air conditioner, performing a first test run to diagnose an assembly state of the air conditioner, performing a second test run to diagnose pipe connection of the air conditioner and an amount of refrigerant in the air conditioner, performing a determination including diagnosing a state of the air conditioner based on operation results of the first test run and the second test run, and displaying the diagnosis result through a display device provided at an indoor unit of the air conditioner.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/817,795 filed on Nov. 20, 2017, which is a continuation of U.S.patent application Ser. No. 13/933,433 filed on Jul. 2, 2013, whichclaims the priority benefit of Korean Patent Application No.10-2012-0072310 filed on Jul. 3, 2012 in the Korean IntellectualProperty Office and Korean Patent Application No. 10-2013-0066054 filedon Jun. 10, 2013 in the Korean Intellectual Property Office, thedisclosures of which are incorporated herein by reference.

BACKGROUND 1. Field

Embodiments relate to a diagnosis control method of an air conditionerthat diagnoses whether the air conditioner has been normally installedand is normally operated.

2. Description of the Related Art

A conventional multi type air conditioner includes two or more indoorunits. Pipes connected between an outdoor unit and the indoor units areinspected to diagnose the air conditioner.

In this case, it is detected whether the air conditioner has not beennormally installed only when a refrigeration cycle is completelyconstrained, for example when refrigerant fully leaks from the airconditioner or when a service valve is fully turned off. As a result,diagnosis of the air conditioner is restricted.

SUMMARY

In an aspect of one or more embodiments, there is provided a diagnosiscontrol method of an air conditioner that clearly informs a user or aninstallation engineer of an installation error which may occur duringinstallation of the air conditioner through diagnosis based on test runsuch that the user or the installation engineer installs the airconditioner and takes follow-up measures with objectivity and accuracy.

In an aspect of one or more embodiments, there is provided a diagnosiscontrol method of an air conditioner which includes receiving a test runcommand or a self-diagnosis command for diagnosis of the airconditioner, performing a first test run to diagnose an assembly stateof the air conditioner, performing a second test run to diagnose pipeconnection of the air conditioner and an amount of refrigerant in theair conditioner, and performing determination including diagnosing astate of the air conditioner based on operation results of the firsttest run and the second test run and displaying the diagnosis resultthrough a display device provided at an indoor unit of the airconditioner.

The performing the first test run may include diagnosing a communicationstate and a component assembly state of the air conditioner.

The performing the second test run may include determining ahigh-pressure clogging error and a refrigerant shortage error of the airconditioner.

The performing the second test run may further include determining, if adifference (Teva_in)−(Teva_in+1) between an inlet temperature (Teva_in)of an indoor heat exchanger of an indoor unit before a compressor of anoutdoor unit is operated and an inlet temperature (Teva_in+1) of theindoor heat exchanger of the indoor unit after the compressor of theoutdoor unit is operated is less than a predetermined reference value,that a pipe connection error has occurred between the outdoor unit andthe indoor unit.

The diagnosis control method may further include determining, if thedifference (Teva_in)−(Teva_in+1) between the inlet temperature (Teva_in)of the indoor heat exchanger before the compressor is operated and aninlet temperature (Teva_in+1) of the indoor heat exchanger after thecompressor is operated is equal to or greater than the predeterminedreference value and a difference (Teva_out)−(Teva_in) between the inlettemperature (Teva_in) and an outlet temperature (Teva_out) of the indoorheat exchanger is greater than a reference degree of superheat, that therefrigerant shortage error has occurred.

The performing the second test run may further include determining, if adifference (Tair_in)−(Teva_in) between an indoor air temperature(Tair_in) and an inlet temperature (Teva_in) of an indoor heat exchangeris equal to or less than a predetermined reference value (Ka) and adifference (Tair_in)−(Teva_out) between the indoor air temperature(Tair_in) and an outlet temperature (Teva_out) of the indoor heatexchanger is equal to or less than another predetermined reference value(Kb), that the high-pressure clogging error has occurred in an outdoorunit.

Conditions to determine the refrigerant shortage error in the secondtest run may include a first determination condition to determine, ifthe inlet temperature (Teva_in) of the indoor heat exchanger is equal toor less than a predetermined reference evaporation temperature (γ), thatthe refrigerant shortage error has occurred, a second determinationcondition to determine, if a difference (Teva_mid)−(Teva_in) between amiddle temperature (Teva_mid) of the indoor heat exchanger and the inlettemperature (Teva_in) of the indoor heat exchanger is equal to orgreater than a predetermined reference degree of evaporator superheat(δ), that the refrigerant shortage error has occurred, and a thirddetermination condition to determine, if a difference (Tdis)−(Tcond)between a discharge temperature (Tdis) of a compressor and an outlettemperature (Tcond) of an outdoor heat exchanger is equal to or greaterthan a predetermined degree of discharged superheat (ε), that therefrigerant shortage error has occurred.

The diagnosis control method may further include detecting, if anoperation time of the compressor exceeds a predetermined time, theindoor air temperature (Tair_in), an outdoor air temperature (Tair_out),the inlet temperature (Teva_in) of the indoor heat exchanger, the middletemperature (Teva_mid) of the indoor heat exchanger, the outlettemperature (Tcond) of the outdoor heat exchanger, and the dischargetemperature (Tdis) of the compressor.

The diagnosis control method may further include determining, if atleast two of the first, second, and third determination conditions aresatisfied, that the refrigerant shortage error has occurred.

The predetermined reference evaporation temperature (γ) of the firstdetermination condition may be a value defined byγ=(Tair_out−35)×0.01×C1+(Tair_in−27)×0.01×C2+C3, where Tair_out is anoutdoor air temperature, Tair_in is an indoor air temperature, and C1,C2, and C3 are constants.

The diagnosis control method may further include changing an operationfrequency of a compressor so as to correspond to the number of indoorunits test running during operation of the compressor.

The diagnosis control method may further include displaying progress ofthe first test run and the second test run through the display device.

The diagnosis control method may further include displaying progress ofthe first test run and the second test run in percentage.

The diagnosis control method may further include announcing progress andcompletion time of the first test run and the second test run using avoice.

The diagnosis control method may further include dividing the first testrun and the second test run into a plurality of processes and displayingprogress of the first test run and the second test run using one of theprocesses.

The display device may include a plurality of light emitting devices andthe diagnosis control method may further include displaying progress ofthe first test run and the second test run by turning on the lightemitting devices.

The diagnosis control method may further include displaying, in aself-diagnosis mode performed by the self-diagnosis command, a messageindicating the self-diagnosis result through the display device.

The performing the first test run may include operating an indoor fanprovided in an indoor unit of the air conditioner to saturate atemperature detector provided in the indoor unit.

The diagnosis control method may further include preventing a lockedstate of the air conditioner from being released such that the operationof the air conditioner is restricted in a case in which test run of theair conditioner has not been performed.

The diagnosis control method may further include resuming the test runif an error occurs during test run of the air conditioner and preventingthe locked state of the air conditioner from being released such thatthe use of the air conditioner is restricted if the test run of the airconditioner is not normally completed.

The diagnosis control method may further include releasing a lockedstate of the air conditioner even when test run of the air conditioneris not normally completed in a self-diagnosis mode performed by theself-diagnosis command.

The diagnosis control method may further include transmittingsetting/installation information to a remote server through a networkmodule to store the setting/installation information in a database if atest run mode performed by the test run command or a self-diagnosis modeperformed by the self-diagnosis command is completed.

The diagnosis control method may further include providing, ifoccurrence of an error is detected in the test run mode or theself-diagnosis mode, a method of resolving the error of the airconditioner and component information necessary to resolve the errorthrough a mobile terminal to provide guidelines to resolve the error.

The diagnosis control method may further include allowing a user to havethorough knowledge of the component information necessary to resolve theerror though provision of the component information when the erroroccurs.

In an aspect of one or more embodiments, there is provided a diagnosiscontrol method of an air conditioner including receiving a test runcommand for diagnosis of the air conditioner; performing a first testrun to diagnose an assembly state of the air conditioner; performing asecond test run to diagnose pipe connection of the air conditioner andan amount of refrigerant in the air conditioner; diagnosing a state ofthe air conditioner based on operation results of the first test run andthe second test run; and displaying the diagnosis result through adisplay device provided at an indoor unit of the air conditioner.

In an aspect of one or more embodiments, there is provided a diagnosiscontrol method of an air conditioner including receiving aself-diagnosis command for diagnosis of the air conditioner; performinga first test run to diagnose an assembly state of the air conditioner;performing a second test run to diagnose pipe connection of the airconditioner and an amount of refrigerant in the air conditioner;diagnosing a state of the air conditioner based on operation results ofthe first test run and the second test run; and displaying the diagnosisresult through a display device provided at an indoor unit of the airconditioner.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of embodiments, taken inconjunction with the accompanying drawings of which:

FIG. 1 is a view showing a refrigeration cycle of an air conditioneraccording to an embodiment;

FIG. 2 is a view showing a control system of the air conditioner shownin FIG. 1;

FIG. 3A is a view showing a diagnosis control method (test run mode) ofan air conditioner according to an embodiment;

FIG. 3B is a view showing a diagnosis control method (self-diagnosismode) of an air conditioner according to an embodiment;

FIG. 4 is a flowchart showing a first test run process of the diagnosiscontrol method shown in FIGS. 3A and 3B;

FIG. 5 is a flowchart showing a second test run process of the diagnosiscontrol method shown in FIGS. 3A and 3B;

FIG. 6A is a flowchart showing an embodiment of a first determinationprocess of the diagnosis control method (test run mode) shown in FIG.3A;

FIG. 6B is a flowchart showing an embodiment of the first determinationprocess of the diagnosis control method (test run mode) shown in FIG.3A;

FIG. 7 is a flowchart showing an embodiment of a second determinationprocess of the diagnosis control method (test run mode) shown in FIG.3A; and

FIG. 8 is a flowchart showing an embodiment of the second determinationprocess of the diagnosis control method (test run mode) shown in FIG.3A.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings, wherein like referencenumerals refer to like elements throughout.

FIG. 1 is a view showing a refrigeration cycle of an air conditioneraccording to an embodiment. As shown in FIG. 1, the air conditioner mayinclude at least one outdoor unit 100 and at least one indoor unit 150.A plurality of indoor units 150 may be connected to one outdoor unit100.

The outdoor unit 100 includes a compressor 102, a four-way valve 104, anoutdoor heat exchanger 106, an electronic expansion valve 154, and anaccumulator 110. The four-way valve 104 is connected to a discharge side102 a of the compressor 102. The four-way valve 104 is controlled suchthat refrigerant discharged from the compressor 102 flows to one side ofthe outdoor heat exchanger 106 during a cooling operation and such thatthe refrigerant discharged from the compressor 102 flows to one side ofthe indoor unit 150 during a heating operation. The other side of theoutdoor heat exchanger 106 is connected to the indoor unit 150. Anoutdoor fan 106 a is installed adjacent to the outdoor heat exchanger106. The accumulator 110 is disposed between a suction side 102 b of thecompressor 102 and the four-way valve 104. A compressor dischargetemperature detector 112 is installed on a refrigerant pipe at thedischarge side of the compressor 102. An outdoor temperature detector114 to detect outdoor temperature is installed at a portion of theoutdoor unit 100. The compressor 102 is a variable capacity compressor.An operation frequency of the compressor 102 is changed so as tocorrespond to capabilities required by the indoor unit 150, wherebycapacity of the compressor 102 is varied.

In FIG. 1, a plurality of indoor units 150 is shown. Some of the indoorunits 150 may be stand type indoor units and some of the indoor units150 may be wall-mount type indoor units. Refrigeration cycle structuresof the indoor units 150 are basically the same. That is, an indoor heatexchanger 152 is provided at each indoor unit 150. An indoor fan 152 ais installed adjacent to the indoor heat exchanger 152. In addition,indoor heat exchanger temperature detectors 156 to detect inlettemperature and middle temperature and outlet temperature of the indoorheat exchanger 152 are installed on refrigerant pipes at opposite sides(inlet and outlet) of the indoor heat exchanger 152. Alternatively, onlyinlet temperature and middle temperature of the indoor heat exchanger152 may be detected or only inlet temperature of the indoor heatexchanger 152 may be detected. In addition, an indoor temperaturedetector 158 to detect indoor temperature is installed at a portion ofthe indoor unit 150.

FIG. 2 is a view showing a control system of the air conditioner shownin FIG. 1. In the outdoor unit 100, the outdoor temperature detector114, the compressor discharge temperature detector 112, a currentdetector 204, a storage device 206, a test run progress rate controller208, a compressor driving controller 210, an outdoor fan controller 212,a four-way valve controller 214, and an electronic expansion valvecontroller 260 are electrically connected to an outdoor unit controller202 in a communicable fashion. In addition, an outdoor unit power supplydevice 216 to supply power to the outdoor unit 100 is provided at theoutdoor unit 100. The outdoor temperature detector 114 and thecompressor discharge temperature detector 112 were previously describedwith reference to FIG. 1. The current detector 204 measures operatingcurrent of the outdoor unit 100. The storage device 206 stores data(regarding a temperature detection value, a valve opening value, etc.)generated during operation of the air conditioner and software necessaryto operate the air conditioner. The test run progress rate controller208 checks a test run progress rate and provides information regardingthe test run progress rate to the outdoor unit controller 202. Theoutdoor unit controller 202 transmits the information regarding the runprogress rate to the indoor unit 150 such that the indoor unit 150displays the progress rate. The compressor driving controller 210controls operation of the compressor 102. The outdoor fan controller 212controls operation (on/off) and rotational speed of the outdoor fan 106a. The four-way valve controller 214 controls opening/closing and anopening degree of the four-way valve 104. The electronic expansion valvecontroller 260 controls an opening degree of the electronic expansionvalve 154 in response to a control command from the outdoor unitcontroller 202.

In the indoor unit 150, the indoor heat exchanger temperature detectors156, the indoor temperature detector 158, an input device 254, an indoorfan controller 256, and a display device 258 are electrically connectedto an indoor unit controller 252 in a communicable fashion. In addition,an indoor unit power supply device 264 to supply power to the indoorunit 150 is provided at the indoor unit 150. The indoor heat exchangertemperature detectors 156 and the indoor temperature detector 158 werepreviously described with reference to FIG. 1. The input device 254allows a user or an engineer to generate a command to control the airconditioner. The input device 254 includes buttons and keys to generatea basic operation control command of the air conditioner. Particularly,the input device 254 includes a test run button 254 a to generate a testrun command. The indoor fan controller 256 controls operation (on/off)and rotational speed of the indoor fan 152 a. The display device 258displays an operation state of the air conditioner and a message orwarning generated during operation of the air conditioner. The displaydevice 258 is provided at the indoor unit 150. Particularly, the displaydevice 258 displays a test run progress rate and a test run result suchthat a user (consumer) may directly recognize the test run result. In acase in which the indoor unit 150 is of a stand type, the display device258 may be a liquid crystal display (LCD) panel. In a case in which theindoor unit 150 is of a wall-mount type, the display device 258 may be alight emitting device, such as a light emitting diode (LED) device. Inaddition, the display device 258 may include a speaker. In a case inwhich the display device 258 is an LCD panel, a test run progress stateof diagnosis control up to now may be displayed as a percentage or thetest run may be divided into 0 to 99 steps and each progress step may bedisplayed. In addition, a graph may be displayed or an inspection resultmay be expressed using a word, such as <normal> or <inspection>. Theword <inspection> indicates that the air conditioner is operatingabnormally and needs to be inspected. In a case in which the displaydevice 258 is an LED device, a plurality of LEDs may be installed suchthat a test run progress degree is displayed based on the number of litLEDs. In a case in which the display device 258 includes a speaker, aprogress degree may be announced using a voice. In addition, a networkmodule 262 to transmit and receive data to and from a remote server isincluded in the indoor unit.

Two-way communication is performed between the outdoor unit 100 and theindoor units 150 shown in FIGS. 1 and 2. Two-way communication is alsoperformed between the indoor units 150. The outdoor unit 100 and theindoor units 150 may exchange various kinds of information generatedduring operation of the air conditioner through such two-waycommunication.

FIG. 3A is a view showing a diagnosis control method (test run mode) ofan air conditioner according to an embodiment. FIG. 3B is a view showinga diagnosis control method (self-diagnosis mode) of an air conditioneraccording to an embodiment. The test run mode of FIG. 3A may be used asa method of checking whether an air conditioner is normally installedwhen the air conditioner is installed for the first time or reinstalledafter removal of the air conditioner. On the other hand, theself-diagnosis mode may be used as a method of a user (or a serviceengineer) directly checking whether an installed state of an airconditioner is normal during use of the air conditioner afterinstallation of the air conditioner. Of course, the service engineer mayuse the self-diagnosis mode and the user may use the test run mode. Thediagnosis control method shown in FIGS. 3A and 3B is performed undercontrol of the outdoor unit controller 202 and the indoor unitcontroller 252 shown in FIG. 2.

In the test run mode of FIG. 3A, when a user (consumer) or aninstallation engineer manipulates the test run button 254 a provided atthe input device 254 of the indoor unit 150 to generate a test runcommand, the indoor unit controller 252 receives the test run commandand transmits the test run command to the outdoor unit controller 202(302). As a result, the indoor unit controller 252 and the outdoor unitcontroller 202 jointly recognize that the test run command has beengenerated.

The diagnosis control method (test run mode) of the air conditionerincludes a first test run process 304, a second test run process 306, afirst determination process 308, and a second determination process 310.In the first test run process 304, an assembly state and a driving stateof various kinds of machinery and equipment and application componentsin the outdoor unit 100 and the indoor unit 150 are checked while theindoor fan 152 a of the indoor unit 150 is operated. In the second testrun process 306, it is checked whether refrigerant normally flowsbetween the indoor unit 100 and each indoor unit 150 while thecompressor 102 of the outdoor unit 100 is operated. In the firstdetermination process 308, it is checked whether a high-pressureclogging error has occurred based on the operation results of the firsttest run process 304 and the second test run process 306. Thehigh-pressure clogging error occurs when a constraint condition, such asvalve locking or expansion valve locking, which disturbs refrigerantcirculation, is met. In the second determination process 310, it isdetermined whether a necessary amount of refrigerant is normallysupplied to each indoor unit 150. The second determination process 310is a refrigerant shortage determination process to determine whetherrefrigerant is normally circulated without clogging and then todetermine whether the amount of refrigerant supplied to each indoor unit150 is sufficient. The first determination process 308 and the seconddetermination process 310 may be combined into a single determinationprocess.

The self-diagnosis mode of FIG. 3B, which is frequently used by a userduring use of the air conditioner after the air conditioner isinstalled, is performed using an entry mode different from the test runmode. In addition, unlike the test run mode, the first determinationprocess is omitted and only the second determination process isperformed in the self-diagnosis mode. The self-diagnosis mode is aninspection mode performed by a user during use of the normally installedair conditioner. Based on the self-diagnosis result, <normal> or<inspection> may be displayed through the display device 258 of theindoor unit. Unlike the test run mode, switching to a locked state isnot performed even when an error occurs. When a user (consumer) or aninstallation engineer manipulates a self-diagnosis button 254 b providedat the input device 254 of the indoor unit 150 to generate aself-diagnosis command, the indoor unit controller 252 receives theself-diagnosis command and transmits the self-diagnosis command to theoutdoor unit controller 202 (352). As a result, the indoor unitcontroller 252 and the outdoor unit controller 202 jointly recognizethat the self-diagnosis command has been generated.

The diagnosis control method (self-diagnosis mode) of the airconditioner includes a first test run process 354, a second test runprocess 356, and a determination process 360. The first test run process354 and the second test run process 356 are performed in the same manneras the first test run process 304 and the second test run process 306 ofthe test run mode. That is, in the first test run process 354, anassembly state and a driving state of various kinds of machinery andequipment and application components in the outdoor unit 100 and theindoor unit 150 are checked while the indoor fan 152 a of the indoorunit 150 is operated. In the second test run process 356, it is checkedwhether a high-pressure clogging error has occurred and a refrigerantshortage error has occurred as previously described while the compressor102 of the outdoor unit 100 is operated. In the determination process360, however, it is determined whether a high-pressure clogging errorhas occurred and then whether a refrigerant shortage error has occurredwithout division into the first determination process and the seconddetermination process.

FIG. 4 is a flowchart showing the first test run process of thediagnosis control method shown in FIGS. 3A and 3B. As shown in FIG. 4,in the first test run process 304, a communication state between theoutdoor unit 100 and the indoor unit 150 is checked and, when checkingof the communication state is completed, a component misassembly stateis checked while the indoor fan 152 a is operated (402). Checking of thecommunication state is possible through checking of a response signalgenerated when the corresponding components are normally operated.Checking of the component misassembly state is also possible throughchecking of a response generated when the corresponding components arenormally assembled. If both the communication state and the componentassembly state are normal (YES of 402), the indoor fan 152 a is operatedto blow air into an air conditioning space in which the indoor unit 150is installed (404). At this time, the electronic expansion valve of eachindoor unit 150 is initialized and the four-way valve 104 of the outdoorunit 100 is closed. The indoor fan 152 a is continuously operated untila predetermined time tn1 is reached (NO of 406). If an operationprogress time of the indoor fan 152 a reaches the predetermined timetn1, entry into the second test run process 304 is performed (YES of406). Here, the indoor fan 152 a is operated for the predetermined timetn1 in a state in which the compressor 102 is stopped because it isnecessary to saturate the temperature detector (that is, the indoor heatexchanger temperature detectors 156 and the indoor temperature detector158) of the indoor unit 150 to the temperature of the air conditioningspace in order to prevent a determination error in a subsequent process.If both the communication state and the component assembly state are notnormal in the process 402 of checking the communication state betweenthe outdoor unit 100 and the indoor unit 150 and the componentmisassembly state (NO of 402), the procedure advances to 606 of thefirst determination process 308, which will hereinafter be described(see FIG. 6).

FIG. 5 is a flowchart showing the second test run process of thediagnosis control method shown in FIGS. 3A and 3B. As shown in FIG. 5,in the second test run process 306, an inlet temperature Teva_in of theindoor heat exchanger 152 is measured through the indoor heat exchangertemperature detectors 156 before the compressor 102 is operated and thenumber of indoor units 150 to be test run is checked (502). The numberof indoor units 150 to be test run may be checked through communicationwith the indoor units 150 which are operated. It is assumed that theindoor units 150 include a stand type indoor unit and a wall-mount typeindoor unit. If both the stand type indoor unit and the wall-mount typeindoor unit are test running, the number of indoor units 150 testrunning is 2. If only the stand type indoor unit or the wall-mount typeindoor unit is currently test running, the number of indoor units 150test running is 1. Subsequently, the electronic expansion valve 154 ofthe indoor unit 150 is opened, and the compressor 102 is operated at anoperation frequency Cf/Cfm corresponding to the number of indoor units150 test running (504). The operation frequency Cf of the compressor 102is an operation frequency of the compressor 102 when only one indoorunit 150 is test run. The operation frequency Cfm of the compressor 102is an operation frequency of the compressor 102 when a plurality ofindoor units 150 is test run. During operation of the compressor 102, itis compared whether the number of indoor units 150 test running is equalto the number of the indoor units 150 having test run (506). If thenumber of indoor units 150 test running is not equal to the number ofthe indoor units 150 having test run (NO of 506), the operationfrequency Cf/Cfm of the compressor 102 is changed so as to correspond tothe number of indoor units 150 test running (508). That is, if thenumber of indoor units 150 test running is greater than the number ofthe indoor units 150 having test run, the operation frequency Cf/Cfm ofthe compressor 102 is increased. On the other hand, if the number ofindoor units 150 test running is less than the number of the indoorunits 150 having test run, the operation frequency Cf/Cfm of thecompressor 102 is decreased. The reason that the operation frequency ofthe compressor 102 is changed based on a single operation or multipleoperations is that the operation frequency of the compressor 102 ischanged based on the sum of operating capacity required by the indoorunits 150 to improve reliability in diagnosis result of the airconditioner and discrimination in determination. If the number of indoorunits 150 test running is equal to the number of the indoor units 150having test run (YES of 506) in the process 506 of comparing whether thenumber of indoor units 150 test running is equal to the number of theindoor units 150 having test run, the compressor 102 is continuouslyoperated without change of the operation frequency Cf/Cfm of thecompressor 102. The compressor 102 is continuously operated until anoperation progress time of the compressor 102 reaches a predeterminedtime tn2 (510). If the operation progress time of the compressor 102reaches the predetermined time tn2 (YES of 510), entry into the firstdetermination process 308 is performed. For reference, the electronicexpansion valve 154 of the indoor units 150 test running remains open ata predetermined fixed opening degree during operation of the compressor102 such that a predetermined amount of refrigerant is supplied to theindoor unit 150. Proper opening values of the electronic expansion valve154 of the indoor units 150 test running are prestored in the storagedevice 206 such that proper opening degrees of the electronic expansionvalve 154 necessary for diagnosis based on model of the air conditionerare maintained.

FIG. 6A is a flowchart showing an embodiment of the first determinationprocess of the diagnosis control method (test run mode) shown in FIG.3A. As previously described with reference to FIG. 5, if the operationprogress time of the compressor 102 reaches the predetermined time tn2(YES of 510), entry into the first determination process 308 isperformed. In the first determination process 308, an inlet temperatureTeva_in+1 of the indoor heat exchanger of the indoor unit 150 testrunning is detected (602). Subsequently, a difference(Teva_in)−(Teva_in+1) between the inlet temperature Teva_in (see 502 ofFIG. 5) of the indoor heat exchanger 152 detected before the compressor102 is operated and the current inlet temperature Teva_in+1 (see 602) ofthe indoor heat exchanger is compared with a predetermined referencevalue Ta (604). If (Teva_in)−(Teva_in+1) is less than the referencevalue Ta (YES of 604), the operations of the indoor fan 152 a and thecompressor 102 are stopped and the first determination result isdisplayed as a pipe connection error on the display device 258 (606).(Teva_in)−(Teva_in+1) being equal to or greater than the reference valueTa indicates that the refrigerant is normally circulated to the indoorunits 150 test running, which indicates that pipe connection between theoutdoor unit 100 and the indoor units 150 test running is normal.Furthermore, this indicates that a refrigerant constraint condition isnot met due to locking of service valve (not shown) or locking of theelectronic expansion valve 154. That is, a high-pressure clogging errordoes not occur. On the other hand, (Teva_in)−(Teva_in+1) being less thanthe reference value Ta indicates that refrigerant is not normallycirculated due to mispiping between the outdoor unit 100 and the indoorunit 150. For reference, even in a case in which both the communicationstate and the component assembly state are not normal (YES of 402) inthe process 402 of checking the communication state between the outdoorunit 100 and the indoor unit 150 and the component misassembly state aspreviously described with reference to FIG. 4, a corresponding error isdisplayed through the display device 258 in the process 606 of FIG. 6.If (Teva_in)−(Teva_in+1) is equal to or greater than the reference valueTa (YES of 604), it is determined that a high-pressure clogging errorhas not occurred and entry into the second determination process 310 isperformed.

FIG. 6B is a flowchart showing another embodiment of the firstdetermination process of the diagnosis control method (test run mode)shown in FIG. 3A. In the first determination process shown in FIG. 6B, astate in which refrigerant is not circulated to each indoor unit 150 dueto two conditions, such as clogging of the air conditioner and completeleakage of the refrigerant, is detected. If the compressor 102 iscontinuously operated in a state in which the refrigerant is notcirculated in the air conditioner, the compressor 102 may be seriouslydamaged, for example burned out. For this reason, if an operation statecorresponding to high-pressure clogging is detected in the test runmode, the operation of the air conditioner is stopped and acorresponding error is displayed. As shown in FIG. 6B, an indoor airtemperature Tair_in is detected (652). The compressor 102 iscontinuously operated until an operation time of the compressor 102reaches a predetermined compressor operation reference time tn (654). Ifthe operation time of the compressor 102 reaches the compressoroperation reference time tn (YES of 654), it is checked whether thecompressor frequency Cf is equal to or greater than a compressor targetfrequency Cf2 (656). If the compressor frequency Cf is greater than thecompressor target frequency Cf2 (YES of 656), an inlet temperatureTeva_in and an outlet temperature Teva_out of the indoor heat exchangerare detected (658). If a difference (Tair_in)−(Teva_in) between theindoor air temperature Tair_in and the inlet temperature Teva_in of theindoor heat exchanger is equal to or less than a predetermined referencevalue Ka and a difference (Tair_in)−(Teva_out) between the indoor airtemperature Tair_in and the outlet temperature Teva_out of the indoorheat exchanger is equal to or less than another predetermined referencevalue Kb (YES of 660), it is determined that the correspondingelectronic expansion valve of the outdoor unit 100 is clogged or therefrigerant has completely leaked, the operation of the compressor 102is stopped (662), and a corresponding error is displayed through thedisplay device 258 (664). On the other hand, if the difference(Tair_in)−(Teva_in) between the indoor air temperature Tair_in and theinlet temperature Teva_in of the indoor heat exchanger is greater thanthe predetermined reference value Ka and the difference(Tair_in)−(Teva_out) between the indoor air temperature Tair_in and theoutlet temperature Teva_out of the indoor heat exchanger is greater thanthe predetermined reference value Kb (NO of 660), it is determined thathigh-pressure clogging has not occurred and entry into the seconddetermination process 310 to determine an amount of the refrigerant isperformed.

FIG. 7 is a flowchart showing an embodiment of the second determinationprocess of the diagnosis control method shown in FIG. 3A. The seconddetermination process shown in FIG. 7 is performed if(Teva_in)−(Teva_in+1) is equal to or greater than the reference value Ta(NO of 604) in the first determination process 308 of FIG. 6. First, if(Teva_in)−(Teva_in+1) is equal to or greater than the reference value Taand the operation time of the compressor 102 is a predetermined time tc(for example, 5 minutes) (YES of 702), the inlet temperature Teva_in andthe outlet temperature Teva_out of the indoor heat exchanger of theindoor unit 150 test running are detected (704).

If the number of the indoor units 150 test running is 1 (YES of 706) anda difference (Teva_out)−(Teva_in) between the inlet temperature Teva_inand the outlet temperature Teva_out of the indoor heat exchanger of thecorresponding indoor unit 150 is less than a reference degree ofsuperheat Tok (YES of 708), the second determination is ended, theoperations of the indoor fan 152 a and the compressor 102 are stopped,and the second determination result is displayed as <normal> on thedisplay device 258 (710).

If the number of the indoor units 150 test running is plural (NO of 706)in the process 706 and the difference (Teva_out)−(Teva_in) between theinlet temperature Teva_in and the outlet temperature Teva_out of theindoor heat exchanger of each indoor unit 150 is less than anotherreference degree of superheat Tokm (YES of 712), the seconddetermination is ended, the operations of the indoor fan 152 a and thecompressor 102 are stopped, and the second determination result isdisplayed as <normal> on the display device 258 (710). If the difference(Teva_out)−(Teva_in) between the inlet temperature Teva_in and theoutlet temperature Teva_out of the indoor heat exchanger is equal to orgreater than the reference degree of superheat Tok or Tokm (NO of 708and 712) in the processes 708 and 712, the procedure advances to theprocess 606 of displaying the first determination result in thepreviously described process 6060 to display a refrigerant shortageerror through the display device 258. If the amount of refrigerantcirculated in a refrigeration cycle of the air conditioner isinsufficient, a gaseous phase rate of refrigerant passing through theindoor heat exchanger 152 is increased due to the characteristics of theindoor heat exchanger 152 in which phase transition of the refrigerantis performed from a liquid phase to a gaseous phase with the result thatthe outlet temperature Teva_out of the indoor heat exchanger isincreased. In addition, the flow rate of a liquid refrigerant introducedinto the inlet of the indoor heat exchanger 152 is decreased with theresult that pressure is lowered and temperature is also decreased.Consequently, the inlet temperature Teva_in of the indoor heat exchangeris decreased and the outlet temperature Teva_out of the indoor heatexchanger is increased. As a result, the degree of superheat is greaterthan a normal level. For this reason, if the difference(Teva_out)−(Teva_in) between the inlet temperature Teva_in and theoutlet temperature Teva_out of the indoor heat exchanger is equal to orgreater than the reference degree of superheat Tok or Tokm (NO of 708and 712), it is determined that the amount of the refrigerant isinsufficient. In a case in which the indoor unit 150 is of a wall-mounttype, only the degree of superheat Tok is applied.

In addition, in a case in which test run of the air conditioner has notbeen performed, a locked state of the air conditioner may not bereleased such that the operation of the air conditioner is restricted.In addition, if an error occurs during test run of the air conditioner,the test run may be resumed. If the test run of the air conditioner isnot normally completed, a locked state of the air conditioner may not bereleased such that the use of the air conditioner is restricted.

FIG. 8 is a flowchart showing another embodiment of the seconddetermination process of the diagnosis control method (test run mode)shown in FIG. 3A. The second determination process shown in FIG. 8 maybe applied in a case in which only the inlet temperature and the middletemperature of the indoor heat exchanger 152 are detected or only theinlet temperature of the indoor heat exchanger 152 is detected. In thesecond determination process shown in FIG. 8, three determinationconditions are applied. If two or more of the determination conditionsare satisfied, it is determined that the amount of refrigerant isinsufficient.

As shown in FIG. 8, the compressor 102 is operated for a predeterminedtime tc (for example, 5 minutes) or more. If the operation time of thecompressor 102 reaches tc (YES of 802), the following temperatures aredetected (804).

Indoor air temperature Tair_in

Outdoor air temperature Tair_out

Inlet temperature Teva_in of indoor heat exchanger

Middle temperature Teva_mid of indoor heat exchanger

Temperature Tcond of outdoor heat exchanger

Discharge temperature Tdis of compressor

If the above temperatures are detected, first, second, and thirdconditions are determined for first error determination (806). First,for the first condition determination, it is checked whether the inlettemperature Teva_in of the indoor heat exchanger is equal to or lessthan a predetermined reference evaporation temperature γ. The referenceevaporation temperature γ is a value defined byγ=(Tair_out−35)×0.01×C1+(Tair_in−27)×0.01×C2+C3 (C1, C2, and C3 beingconstants decided based on characteristics of the air conditioner). Thefirst determination condition is used to measure the inlet temperatureTeva_in of the indoor heat exchanger to determine whether a refrigerantlevel is insufficient, uses a principle in which the inlet temperatureof the indoor heat exchanger is decreased if the refrigerant isinsufficient. After the compressor 102 is started, the inlet temperatureTeva_in of the indoor heat exchanger is measured. If the inlettemperature Teva_in of the indoor heat exchanger is equal to or lessthan a predetermined value, it is determined that the amount of therefrigerant is insufficient. The predetermined value is changed based onthe indoor air temperature Tair_in and the outdoor air temperatureTair_out.

Subsequently, for the second condition determination, it is determinedwhether refrigerant is insufficient based on a difference(Teva_mid)−(Teva_in) between the middle temperature Teva_mid of theindoor heat exchanger and the inlet temperature Teva_in of the indoorheat exchanger. That is, it is checked whether the difference(Teva_mid)−(Teva_in) between the middle temperature Teva_mid of theindoor heat exchanger and the inlet temperature Teva_in of the indoorheat exchanger is equal to or greater than a predetermined referencedegree of evaporator superheat δ. In the second determination condition,if the difference (Teva_mid)−(Teva_in) between the middle temperatureTeva_mid of the indoor heat exchanger and the inlet temperature Teva_inof the indoor heat exchanger is greater than the reference degree ofevaporator superheat δ, it is determined that the amount of refrigerantcirculated in the indoor unit 150 is insufficient. If the amount ofrefrigerant circulated in the refrigeration cycle of the air conditioneris insufficient, a gaseous phase rate of refrigerant passing through theindoor heat exchanger 152 is increased due to the characteristics of theindoor heat exchanger 152 in which phase transition of the refrigerantis performed from a liquid phase to a gaseous phase with the result thatthe outlet temperature Teva_out of the indoor heat exchanger isincreased. In addition, the flow rate of a liquid refrigerant introducedinto the inlet of the indoor heat exchanger 152 is decreased with theresult that pressure is lowered and the inlet temperature Teva_in of theindoor heat exchanger is also decreased. Consequently, the inlettemperature Teva_in of the indoor heat exchanger is decreased and theoutlet temperature Teva_out of the indoor heat exchanger is increased.As a result, the degree of superheat is greater than a normal level.Even in a case in which the temperature detector is not attached to theoutlet but to the middle portion of the indoor heat exchanger 152, thedifference between the middle temperature Teva_mid of the indoor heatexchanger and the inlet temperature Teva_in of the indoor heat exchangeris greater than a normal level when the refrigerant level isinsufficient. For this reason, it is determined whether the refrigerantlevel is insufficient using the middle temperature Teva_mid of theindoor heat exchanger instead of the outlet temperature Teva_out of theindoor heat exchanger

Subsequently, for the third condition determination, it is determinedwhether a refrigerant level is insufficient based on a difference(Tdis)−(Tcond) between the discharge temperature Tdis of the compressorand the outlet temperature Tcond of the outdoor heat exchanger. That is,it is checked whether the difference (Tdis)−(Tcond) between thedischarge temperature Tdis of the compressor and the outlet temperatureTcond of the outdoor heat exchanger is equal to or greater than apredetermined degree of discharged superheat ε. If the compressor isoperated in a state in which the refrigerant level is insufficient, thedischarge temperature Tdis of the compressor is increased with theresult that the difference (Tdis)−(Tcond) between the dischargetemperature Tdis of the compressor and the outlet temperature Tcond ofthe outdoor heat exchanger is greater than a normal level, which is usedin the third determination condition.

If it is determined that at least two of the first, second, and thirddetermination conditions are satisfied (YES of 811), the operations ofthe indoor fan 152 a and the compressor 102 are stopped and the seconddetermination result is displayed as a refrigerant shortage error on thedisplay device 258 (814). On the other hand, if it is determined that atleast two of the first, second, and third determination conditions arenot satisfied (NO of 811), it is determined that the refrigerant levelis sufficient, the operations of the indoor fan 152 a, the outdoor fan106 a, and the compressor 102 are stopped, and <normal> is displayed onthe display device 258 (812).

In FIG. 8, the first determination condition, the second determinationcondition, and the third determination condition are performed as oneprocess. Alternatively, determination of the first determinationcondition, the second determination condition, and the thirddetermination condition may be partially omitted or the sequence of thefirst determination condition, the second determination condition, andthe third determination condition may be changed based on the followingconditions. For example, in the first condition determination process,if the inlet temperature Teva_in of the indoor heat exchanger is equalto or less than the reference evaporation temperature γ it may bedetermined that the refrigerant level is insufficient and the thirdcondition determination may be performed. In the first conditiondetermination process, on the other hand, if the inlet temperatureTeva_in of the indoor heat exchanger is greater than the referenceevaporation temperature γ, the second condition determination may beperformed.

In the second condition determination process, if the difference(Teva_mid)−(Teva_in) between the middle temperature Teva_mid of theindoor heat exchanger and the inlet temperature Teva_in of the indoorheat exchanger is equal to or greater than the reference degree ofevaporator superheat δ, the third condition determination may beperformed. In the second condition determination process, on the otherhand, If the difference (Teva_mid)−(Teva_in) between the middletemperature Teva_mid of the indoor heat exchanger and the inlettemperature Teva_in of the indoor heat exchanger is less than thereference degree of evaporator superheat δ it may be determined that therefrigerant level is sufficient, the operations of the indoor fan 152 a,the outdoor fan 106 a, and the compressor 102 may be stopped, and<normal> may be displayed on the display device 258 (812).

In the third condition determination process, if the difference(Tdis)−(Tcond) between the discharge temperature Tdis of the compressorand the outlet temperature Tcond of the outdoor heat exchanger is lessthan the degree of discharged superheat ε, it may be determined that therefrigerant level is sufficient, the operations of the indoor fan 152 a,the outdoor fan 106 a, and the compressor 102 may be stopped, and<normal> may be displayed on the display device 258 (812). In the thirdcondition determination process, on the other hand, if the difference(Tdis)−(Tcond) between the discharge temperature Tdis of the compressorand the outlet temperature Tcond of the outdoor heat exchanger is equalto or greater than the degree of discharged superheat ε, the operationsof the indoor fan 152 a and the compressor 102 may be stopped and thesecond determination result may be displayed as a refrigerant shortageerror on the display device 258 (814).

As is apparent from the above description, in an aspect of embodiments,a diagnosis control method of an air conditioner may clearly inform auser or an installation engineer of an installation error which mayoccur during installation of the air conditioner through diagnosis basedon test run such that the user or the installation engineer installs theair conditioner and takes follow-up measures with objectivity andaccuracy, thereby improving installation quality and completeness duringinstallation of the air conditioner and thus improving customersatisfaction.

In addition, a user or a service engineer may determine whether theamount of refrigerant is sufficient using a self-diagnosis mode afterthe test run is normally completed during installation of the airconditioner, thereby performing inspection of the air conditioner duringuse of the air conditioner.

In addition, setting/installation information of the air conditioner maybe transmitted to a specific remote server using a network (for example,a W-Fi network) through a network module and stored in a database afterthe test run mode or the self-diagnosis mode is completed, therebyachieving construction of a network between the air conditioner and theserver.

In addition, if an error occurs during execution of the test run mode orthe self-diagnosis mode, a service engineer may check a serial number(S/N) of the air conditioner using a mobile terminal, such as asmartphone and, correspondingly, the air conditioner may inform theservice engineer of a method of resolving a corresponding test run errorand information (database code, 3D image, etc.) of a correspondingdefective component to provide the service engineer with guidelines toresolve the error and enable the service engineer to order a componentto be replaced.

In a case in which a problem is encountered during use of the airconditioner, a user may transmit corresponding operation information ofthe air conditioner to a server and a mobile terminal of the user. Whena service call is made, a service engineer may visit the user afterpreviously having thorough knowledge of an operation state andinformation of the air conditioner. In a case in which a defectivecomponent is to be replaced, therefore, the service engineer may preparea substitute, thereby preventing additional visit and thus reducingservice expenses and improving customer satisfaction.

Although a few embodiments have been shown and described, it would beappreciated by those skilled in the art that changes may be made inthese embodiments without departing from the principles and spirit ofthe disclosure, the scope of which is defined in the claims and theirequivalents.

What is claimed is:
 1. An air conditioner comprising: an indoor unitincluding an indoor fan and an indoor heat exchanger; an outdoor unitconfigured to be connected to the indoor unit by at least onerefrigerant pipe, and including a compressor; and a controllerconfigured to receive a test run command to perform a test run includinga first test run and a second test run, control the air conditioner toperform the first test run by operating the indoor fan of the indoorunit when the indoor unit is connected to the outdoor unit by the atleast one refrigerant pipe, control the air conditioner to perform thesecond test run by operating the compressor of the outdoor unit, anddiagnose whether a valve of the air conditioner is clogged based on afirst inlet temperature of the indoor heat exchanger before thecompressor is operated in the second test run and a second inlettemperature of the indoor heat exchanger after the compressor isoperated in the second test run.
 2. The air conditioner according toclaim 1, wherein the controller is further configured to provide atleast one value, based on the at least one of the result of the firsttest run and the result of the second test run, which is used todetermine whether or not a service valve of the air conditioner islocked.
 3. The air conditioner according to claim 1, wherein thecontroller is configured to determine whether or not a service valve ofthe air conditioner is locked based on the at least one of the result ofthe first test run and the result of the second test run.
 4. The airconditioner according to claim 1, wherein the controller is furtherconfigured to provide at least one value, based on the at least one ofthe result of the first test run and the result of the second test run,which is used to determine whether or not an amount of refrigerant inthe air conditioner is insufficient.
 5. The air conditioner according toclaim 1, wherein the controller is further configured to determinewhether an amount of refrigerant in the air conditioner is insufficientbased on the at least one of the result of the first test run and theresult of the second test run.
 6. The air conditioner according to claim1, wherein the controller is further configured to provide a signal,based on the result of the first test run, which is used to diagnose anassembly state of the air conditioner.
 7. The air conditioner accordingto claim 1, wherein the controller is further configured to diagnose acommunication state between the indoor unit and the outdoor unit whileperforming the test run.
 8. The air conditioner according to claim 1,wherein the controller is further configured to prevent a locked stateof the air conditioner from being released until the first test run andthe second test run are completed.
 9. The air conditioner according toclaim 1, further comprising: an input interface configured to receive aninput and transmit the test run command to the controller.
 10. The airconditioner according to claim 1, wherein the controller is furtherconfigured to diagnose whether the valve of the air conditioner isclogged when a difference between the first inlet temperature of theindoor heat exchanger before the compressor is operated in the secondtest run and the second inlet temperature of the indoor heat exchangerafter the compressor is operated in the second test run is less than apredetermined reference value.
 11. The air conditioner according toclaim 1, wherein the valve of the air conditioner includes at least oneof a service valve and an expansion valve.
 12. A diagnosis controlmethod of an air conditioner including an indoor unit including anindoor fan and an indoor heat exchanger, and an outdoor unit including acompressor, the method comprising: receiving, by a controller of the airconditioner, a test run command, to perform a test run including a firsttest run and a second test run, after the indoor unit is connected tothe outdoor unit by at least one refrigerant pipe; controlling, by thecontroller of the air conditioner, the indoor unit to perform the firsttest run by operating the indoor fan of the indoor unit; controlling, bythe controller of the air conditioner, the outdoor unit to perform thesecond test run by operating the compressor of the outdoor unit; anddiagnosing, by the controller of the air conditioner, whether a valve ofthe air conditioner is clogged based on a first inlet temperature of theindoor heat exchanger before the compressor is operated in the secondtest run and a second inlet temperature of the indoor heat exchangerafter the compressor is operated in the second test run.
 13. The methodaccording to claim 12, wherein the diagnosing comprises: providing atleast one value, based on at least one of the result of the first testrun and the result of the second test run, which is used to determinewhether or not a service valve of the air conditioner is locked.
 14. Themethod according to claim 12, wherein the diagnosing comprises:determining, by the controller of the air conditioner, whether or not aservice valve of the air conditioner is locked based on at least one ofthe result of the first test run and the result of the second test run.15. The method according to claim 12, wherein the diagnosing comprises:providing at least one value, based on the at least one of the result ofthe first test run and the result of the second test run, which is usedto determine whether an amount of a refrigerant of the air conditioneris insufficient.
 16. The method according to claim 12, wherein thediagnosing comprises: determining, by the controller of the airconditioner, whether an amount of a refrigerant of the air conditioneris insufficient based on the at least one of the result of the firsttest run and the result of the second test run.
 17. The method accordingto claim 12, further comprising: providing a signal, based on the resultof the first test run, which is used to diagnose an assembly state ofthe air conditioner.
 18. The method according to claim 12, furthercomprising: diagnosing, by the controller of the air conditioner, acommunication state between the indoor unit and the outdoor unit whileperforming the test run.
 19. The method according to claim 12, furthercomprising: preventing, by the controller of the air conditioner, alocked state of the air conditioner from being released until the firsttest run and the second test run are completed.